Considering a bow thruster; best choices?

[ranger58sb]

Somebody in our family recently suggested a bow thruster might make that somebody's job slightly easier while docking... so just in case a bow thruster project bubbles up to the top of my wallet anytime soon...

So without debating whether they're useful or not... without considering hydraulic thrusters or genset PTO options... and without considering external thrusters...

And assuming I'd probably prefer a 24V tunnel system with dedicated AGM batteries located very near the bow thruster, probably with a dedicated 24V own charger... in our 42' 28K-lbs boat...

I thought it might be useful to start with a "market survey" of sorts.

I've only superficially looked at options like the Imtra/Side-Power SE80 and the Vetus/Maxwell BOW7524D, without lots of time comparing thrusters to boat sizes/weights yet. I assume there might be decent options from Lewmar, Max Power, maybe others...

Who's got a thruster? Which one (brand/model)? In what boat?

Comments about horsepower vs. boat size? About single prop vs. dual prop? Good or bad about various brands or designs?

-Chris

 

[caltexflanc]

I give Florida Bow Thrusters, the Vetus distributor and installer, my highest recommendation. They install all over the country and I have seen their excellent work first hand at various yards. Also have met many happy customers. I have personally experienced their terrific way-way-way after the sale customer service first hand.

 

[av8r]

We have the same set-up as you describe with the SE-120. The installation was done by North Harbor Diesel in Anacortes and we were very pleased with the service, the installation, and the product.

 

[Chrisjs]

Not meaning to take the thread off course, but a question about best bow thruster batteries. We had a similar set up to the one envisaged with 2 dedicated 4D batteries providing 24V. They were deep cycle (house-type) batteries. While it was never really an issue, my question is whether it would be better to power with starter type batteries (not deep cycle). Logic being that the thruster is basically a big starter motor that draws a lot of current for a short period of time.

 

[O C Diver]

I've been very happy with Side-Power and there US distributor Imtra. They were very helpful with my conversion from 12 to 24 volts (motor replacement) and pointing me to a dealer who would sell me the motor well below retail.

If you go with the 7.3" tunnel and choose the Side-Power SE80 over the SE100, you're certifiably insane. The difference in cost between the 2 when looking at the total cost of the installation, is a rounding error at most. Remember, nobody ever said, " I wished I'd bought a smaller bow thruster ". For that tunnel size with your boat, regardless of manufacturer, I would buy the most powerful thruster that fits that tunnel.

Ted

 

[GFC]

OC Diver's last sentence really sums up what I was going to say. Go with the biggest tunnel you can fit on your boat and stuff it with the most powerful thruster you can.


Nobody ever said "Gee, I wish my thruster didn't have so much power".

 

[dhays]

As Ted and Mike said, put the largest thruster you can reasonably install. You will rarely need the extra power, but when you do you will appreciate it. A couple months ago I ran into a situation where my bow and stern thrusters were not sufficient to overcome wind and current. I would have appreciated a bit more thrust in that situation.

 

[Comodave]

I have a Side Power thruster that I installed in the stern of our 42’ trawler. Works extremely well. Have had good customer service from Imtra. I do not have room for an internal bow thruster. May install an external bow thruster. Was going to do it this winter but went with quartz countertops for our house instead... I agree that you should go big or stay home. I went one size larger on my stern thruster and certainly do not regret it. 35 to 40 mph winds had my boat pinned to the dock and I needed to reposition a fender. I could not budge the boat even a 1/4” by pushing it with everything I had and then I thought about the thruster. It moved the boat upwind immediately.

 

[Ski in NC]

I put a Sidepower bow thruster in about 2010. It works well and has been reliable.

 

[Woodland Hills]

18hp Wesmar........

 

[BobnDoc]

A related issue
Several of us here on Puget Sound have been having trouble with
erratic performance of our Lewmar bow thrusters. They go off on their own. This has happened while underway and when moored. Two of us have one year old Cutwater 30cb. The other guy has had three sets of thruster motors and control units replaced. He seems to think a new model control unit may have solved the problem. I’m still waiting for a new lower control unit to arrive. In the meantime I’m considering an excorcism to rid my bow thruster of the demons possessing it.

 

[ranger58sb]

If you go with the 7.3" tunnel and choose the Side-Power SE80 over the SE100, you're certifiably insane. The difference in cost between the 2 when looking at the total cost of the installation, is a rounding error at most. Remember, nobody ever said, " I wished I'd bought a smaller bow thruster ". For that tunnel size with your boat, regardless of manufacturer, I would buy the most powerful thruster that fits that tunnel.

Sounds like a fair point, although I'm sometimes sensitive to the magnitude of some rounding errors. And I'm probably not qualified to say whether I'm certifiable or not.

Using Defender's prices as examples, I see they want $2695 for the SE80 and $3640 for the SE100.

-Chris

 

[O C Diver]

Sounds like a fair point, although I'm sometimes sensitive to the magnitude of some rounding errors. And I'm probably not qualified to say whether I'm certifiable or not.

Using Defender's prices as examples, I see they want $2695 for the SE80 and $3640 for the SE100.

-Chris

Ok, I was looking at Imtra's site and saw a $1,300 difference on a $5,200 thruster. Figuring you would be looking at 5 figures all in, $1,300 wasn't significant.

Did you get an estimate on installing the tunnel?

Ted

 

[Comodave]

I found the lowest price at Marine Wharehouse on my Side Power thruster. No affiliation just satisfied customer.

 

[ranger58sb]

Ok, I was looking at Imtra's site and saw a $1,300 difference on a $5,200 thruster. Figuring you would be looking at 5 figures all in, $1,300 wasn't significant.

Did you get an estimate on installing the tunnel?

In the grand scheme of things... you might well be right about what's significant.

Today is the first I've really thought of pursuing the whole idea... since it was just last evening I was informed it might be a good idea... so, no, haven't yet got anything more than hearsay about installation costs.

I'm guessing all in, thruster, assuming two Odyssey PC-2150s in series to 24V, a 24V charger, and some whiz-bang nifty controls, plus installation (including the tunnel)... maybe 2.5-3x the cost of just the thruster.

??

-Chris

 

[ranger58sb]

I found the lowest price at Marine Wharehouse on my Side Power thruster. No affiliation just satisfied customer.

Thanks, that's useful.


Anybody know about Max-Power thrusters? They seem to be less expensive than Vetus or Side-Power units of similar thrust... and at least one installer suggest he likes 'em because they're more corrosion-resistant.

??

-Chris

 

[Cyclone]

Has anyone installed a “Yacht Thruster”? Give their apparent ease of installation, no large hole, they seem to me to be the way to go to handle both bow and stern issues.

 

[Comodave]

Not yet but I will probably install one on our bow in the future. We do not have room in the bow for a traditional tunnel.

 

[O C Diver]

In the grand scheme of things... you might well be right about what's significant.

Today is the first I've really thought of pursuing the whole idea... since it was just last evening I was informed it might be a good idea... so, no, haven't yet got anything more than hearsay about installation costs.

I'm guessing all in, thruster, assuming two Odyssey PC-2150s in series to 24V, a 24V charger, and some whiz-bang nifty controls, plus installation (including the tunnel)... maybe 2.5-3x the cost of just the thruster.

??

-Chris

Chris, I'm not an expert on bow thruster installations, nor have I ever played an installer on TV, however, this is what I know:

Installing the tube is not rocket science for a good fiberglass man. On a displacement hull boat, it's not that bad a job. Sean the guy who did the fiberglass and paint work on my refit has done one or two. I watched him do one and if you can figure out where the hole goes, the rest is fiberglass work.

With a planing hull there's more to putting the tube in. The placement is more critical and the eyebrow effect around the hole is important for hull performance when on plane. Simply, you want to make darn sure the installer has done a number of planing hulls including ones in your size.

While I'm just guessing from my armchair, a complete install from a bow thruster installer, soup to nuts, $15K. Hope it's less.

Ted

 

[Comodave]

It isn’t that hard to figure out the hole placement. Measure the inside and mark the centerline for the hole on each side. Tape a rare earth magnet on the inside and then go outside with another magnet and it will locate very quickly. Drill a pilot hole on each side. Take a long rod and bend the end into a J equal to the radius of the tube. Run the J in a circle to mark the cut line and cut it horizontally with a jig saw or your choice of saw. Then glass the tube in. The glass work is the easy part.

 

[Heron]

The glass work is the easy part.

I've seen some good YouToob tutorials...

 

[ranger58sb]

I think I'm not wanting to be taking Fiberglass-101 on a job like this...

I understand the concept, but have no experience or skill...

-Chris

 

[High Wire]

The best choice is those that you can get service and parts for anywhere you cruise. I have a Vetus that is close to 30 years old, and except for a cracked oil reservoir hose, has been flawless.

 

[ranger58sb]

Using the "largest for the tunnel" theory, a quick market survey suggests Side-Power SE100, Vetus BOW95, or Max-Power CT125 are likely candidates. The latter seems surprisingly less expensive than the Side-Power or Vetus. Reason?

-Chris

 

[wkearney99]

My take on thrusters is plan to dock like you don't have them and use them sparingly. This way you minimize battery capacity problems. Especially if you have twin engines. Use those engines and save the thruster until you really need the added sideways bump.

With a single engine or in more challenging docking conditions it'd be different. If you'd be fighting against a lot of tide, current or winds on a regular basis then larger battery capacity, 24v or going hydraulic, is definitely worth considering. But for around here on the Chesapeake conditions are usually mild enough to not have to get into extremes.

 

[ranger58sb]

My take on thrusters is plan to dock like you don't have them and use them sparingly. This way you minimize battery capacity problems. Especially if you have twin engines. Use those engines and save the thruster until you really need the added sideways bump.

With a single engine or in more challenging docking conditions it'd be different. If you'd be fighting against a lot of tide, current or winds on a regular basis then larger battery capacity, 24v or going hydraulic, is definitely worth considering. But for around here on the Chesapeake conditions are usually mild enough to not have to get into extremes.

Yeah... but I'm not really debating whether I need a thruster or whether they're useful... or in what conditions. I've got enough experience with twins and a single to not really be bothered about all that...

At this point, it's just a question of "If I want a thruster, which do I get?" I've eliminated AC- or hydraulic-powered units as probably being more complex than I would want to fool with. Likely more expensive, too, but that's just a guess.

Then it also comes close to a question of a "Is 12V sufficient or is 24V (in a 12V boat) enough better to warrant the extra cost?"

Either way, I think I'll maybe need (or want) a new charger, maybe dedicated only to the thruster bank, and in that scenario... especially if a new charger could likely be co-located with the thruster bank and the thruster bank is colocated with the thruster... the difference between 12V and 24V may be a wash, cost-wise. I'm kind of debating this part with myself, as we speak.

We currently have an older 40-amp 12V charger dedicated to our port dual-purpose bank, and a 70-amp 12V inverter/charger dedicated to our starboard dual purpose bank.

Neither of those chargers is large enough to meet the two battery makers' recommendations for ideal minimum charging current... although they're "OK enough" at least for now. If the older 40-amp charger goes south, I'd likely replace it with a 60-amp unit, which may mean new wiring and still wouldn't meet recommendations for ideal minimum charging level for that bank.

Anyway, that kind of stuff is what's going through my mind just now...

High Wire makes an excellent point about being able to get service, in various places.

Which makes me ask if service possibilities on Side-Power, Vetus, or Max-Power units is roughly equal, or if one/some are much better than another?

-Chris

 

[Comodave]

I added a 15 amp Promariner battery charger just for the stern thruster. It works well even though the battery only get charged when we are plugged into the dock or running the genset. I have an Optima battery for it. When I put in a bow thruster I will go with a 24 volt thruster. I plan on using 2 Optimas in series and install a separate 24 volt Promariner charger for that bank. As to which thruster is best, I only have experience with Side Power. I suspect most people only have experience with one brand and therefore won’t be able to say which one is best.

 

[TomandJeri]

At this point, it's just a question of "If I want a thruster, which do I get?" I've eliminated AC- or hydraulic-powered units as probably being more complex than I would want to fool with. Likely more expensive, too, but that's just a guess.

Then it also comes close to a question of a "Is 12V sufficient or is 24V (in a 12V boat) enough better to warrant the extra cost?"

My FIL had a thruster installed in his KK42 decades ago when it was new, and rarely ever used it. I asked why not once, and he said that it mainly made a lot of noise and drew the battery down, so he didn't bother. I have no idea if it was 12 or 24V. But the take-away for me was, if you're going to spend the money to buy and have a yard install one (they charged him for all the core drills they wore out getting through that thick hull), make it big enough to actually be useful, even though it costs more than one just big enough to make noise and draw the battery down. Otherwise, you're just wasting your money.

 

[O C Diver]

Regarding chargers, my choice was a simple dual bank 12 volt 6 amp battery charger that is fed off either the pure sine wave inverter, generator or shore power. My thruster is two 12 volt optima batteries in series. If you do the math on how many amps they draw, for how many seconds you're going to be able to use it, and then convert that to amps per hour, you will realize you use very little killowatts. Whats deceptive is the size of the batteries to be able to deliver the required amps for less than a minute.

This is the charger I have.

https://www.batterystuff.com/batter...bank-marine-waterproof-smart-charger-rs2.html

Ted

 

[Gmwalley]

just contracted for thrusters for my boat

Went with Docking by Control out of Florida. Came recommended by my yard manager. So far been great to work with - answered ALOT of questions and made me feel comfortable. They also recommend biggest / baddest thruster you can fit, incremental cost for up-sized thrusters is small when comparing total job costs. I am having the new proportional control RIM-DRIVE Vetus thrusters with 48V battery banks / chargers and dual controls. Boat is a 60,000 lb, Tollycraft 53 with significant windage. Install is scheduled for first week in OCT. Total price not including bottom paint and other work happening at same time is ~$35,000 all in. Florida Bow thrusters bit was nearly $10,000 more for same thing except single battery bank / charger. Will post on how it all worked out!